Project Summary/Abstract The substance abuse treatment field faces an unprecedented challenge to reduce health disparities among racial and ethnic minority populations. Access to integrated substance abuse, mental health, and HIV prevention care is associated with positive health outcomes and reduced cost. The overall goal of the proposed study is to identify how changes precipitated by the Affordable Care Act (ACA) impact community- based outpatient substance abuse treatment (OSAT) program capacity to expand service delivery in racial and ethnic minority communities and eliminate outcome disparities among African American and Latino clients. The objective for this application is to examine the organizational impact of the current expansion of Medicaid on the capacity of community-based OSAT programs to enhance treatment access and retention among minorities residing in Los Angeles County (L.A.), California by developing and analyzing a panel dataset. Our conceptual framework, grounded in organizational development frameworks investigates the role of organizational capacity (i.e., leadership, readiness for change, Medi-Cal billing) in mediating the effect of Medicaid expansion (referred as Medi-Cal in California) on service delivery (i.e., mental health and HIV prevention services) and on treatment access and retention among African American and Latino clients. In Aim 1 and 2 we will examine baseline data to refine our conceptual model of organizational capacity factors likely to impact the delivery of mental health and HIV prevention services in OSAT programs in racial and ethnic minority communities, prior to ACA enactment. We will resurvey in 2013, 2015 and 2017 the same representative sample of 147 OSAT programs located in minority communities to form a panel data set. These repeated measures of program data will be concatenated with administrative client outcome data (N~10,800 clients) at each data point to examine in Aims 3 and 4 the longitudinal impact of insurance expansion on service delivery in minority communities and rates of access and retention among African American and Latino clients with mental health and HIV risk conditions. The overall public health impact of the proposed study includes identifying promising organizational factors among publicly funded community-based OSAT programs that serve large proportions of low-income minority clients that play a mediating role between the ACA insurance expansion and client-centered process outcomes with the goal of eliminating health disparities.